CONSTRICTED DISLOCATIONS AND THEIR USE FOR TEM MEASUREMENTS OF THE VELOCITIES OF EDGE AND 60-DEGREES DISLOCATIONS IN SILICON - A NEW APPROACH TO THE PROBLEM OF KINK MIGRATION

A new method of measuring dislocation velocities in the bulk by TEM is presented. Jogs on dislocations are strong obstacles against dislocat ion motion during a low temperature deformation. They can be used as m arkers for the initial course of the dislocation lines and allow to me asure the paths travelled by the free dislocation segments between the jogs. First results for the activation energy of the motion of screws and 60-degrees dislocations (2 eV) and for the edges (1.8 eV) are rep orted. An edge dislocation is assumed to be a series of geometrical ki nks. Its motion is interpreted as the collective motion of kinks and t he activation energy is tentatively attributed to the kink migration e nergy.